1. Field of the Invention
The present invention relates to a vehicle-body assembly line and a method for assembling a vehicle body. The present invention relates in particular to a vehicle-body assembly line and a method for assembling a vehicle body in which a vehicle body is placed on a base provided on a carrier for placing a vehicle body, and components are assembled to the vehicle body while the carrier is conveyed downstream.
2. Description of the Related Art
Patent Document 1 (Japanese Patent Application Laid-open No. H04-358976) discloses the following vehicle body assembly method. The vehicle body assembly method includes: a step of removing doors from a vehicle body on which coating is completed, and conveying the doors through a conveyor system to a first door storage apparatus; a step of taking out the doors from the first door storage apparatus to a door assembly line and assembling door components to the doors in the door assembly line; a step of conveying to a second door storage apparatus the doors to which the door components are assembled; and a step of taking out the doors from the second door storage apparatus, conveying the doors to an assembly area in which the doors are to be assembled to the vehicle body to which components assembly is completed, and assembling the doors to the vehicle body.
However, according to the technique disclosed in Patent Document 1, the conveyor system for the doors is required to be arranged, for example, between the stage of removing the doors from the vehicle body and the first door storage and between the second door storage and the stage of assembling the door to the vehicle body. Therefore, production of a door-conveyor hanger and construction of a conveyor are required, so that the cost is increased. In addition, the above technique needs a very large space for the construction of the conveyor. Further, the above technique needs separate construction of an door-component assembly line for assembling components to the doors removed from the vehicle body, so that the cost is increased.
The object of the present invention is to provide a vehicle-body assembly line and a method for assembling a vehicle body which enable cost reduction, space saving, and return of a door to a vehicle body after removal of the door from the vehicle body and assembly of a component to the door.